Orbit determination

Tests of general relativity

Physics

Gravitation

Geology

Doppler effect

GNSS applications

Aerospace engineering

Gravitational redshift

Galaxy

Astronomy

Engineering

Satellite

Galileo (satellite navigation)

Orbit (dynamics)

Astrophysics

Redshift

Remote sensing

Physical Review Letters

On August 22, 2014, the satellites GSAT-0201 and GSAT-0202 of the European GNSS Galileo were unintentionally launched into eccentric orbits. Unexpectedly, this has become a fortunate scientific opportunity since the onboard hydrogen masers allow for a sensitive test of the redshift predicted by the theory of general relativity. In the present Letter we describe an analysis of approximately three years of data from these satellites including three different clocks. For one of these we determine the test parameter quantifying a potential violation of the combined effects of the gravitational redshift and the relativistic Doppler shift. The uncertainty of our result is reduced by more than a factor 4 as compared to the values of Gravity Probe A obtained in 1976.

Test of the Gravitational Redshift with<i>Galileo</i>Satellites in an Eccentric Orbit

Test of the Gravitational Redshift withGalileoSatellites in an Eccentric Orbit